Fire effects on soils: the human dimension

Abstract

Soils are among the most valuable non-renewable resources on the Earth. They support natural vegetation and human agro-ecosystems, represent the largest terrestrial organic carbon stock, and act as stores and filters for water. Mankind has impacted on soils from its early days in many different ways, with burning being the first human perturbation at landscape scales. Fire has long been used as a tool to fertilize soils and control plant growth, but it can also substantially change vegetation, enhance soil erosion and even cause desertification of previously productive areas. Indeed fire is now regarded by some as the seventh soil-forming factor. Here we explore the effects of fire on soils as influenced by human interference. Human-induced fires have shaped our landscape for thousands of years and they are currently the most common fires in many parts of the world. We first give an overview of fire effect on soils and then focus specifically on (i) how traditional land-use practices involving fire, such as slash-and-burn or vegetation clearing, have affected and still are affecting soils; (ii) the effects of more modern uses of fire, such as fuel reduction or ecological burns, on soils; and (iii) the ongoing and potential future effects on soils of the complex interactions between human-induced land cover changes, climate warming and fire dynamics. This article is part of the themed issue ‘The interaction of fire and mankind’.

Global trends in wildfire and its impacts: perceptions versus realities in a changing world

“…Post-fire environmental effects such as accelerated flooding, soil erosion, mass movement and pollution of water bodies are among the most costly impacts on society [3,62,63]. Other important indirect effects are the longer-term health implications [95].…”

“…The fact that nowadays the latest news reports about disasters from around the world are readily available to large parts of the population may be a contributing factor. What is not spreading equally well is the recognition that fire is a fundamental natural ecological agent in many of our ecosystems and only a 'problem' where we choose to inhabit these fireprone regions or we humans introduce it to non-fire-adapted ecosystems [3]. The 'wildfire problem' is essentially more a social than a natural one.…”

Living on a flammable planet: interdisciplinary, cross-scalar and varied cultural lessons, prospects and challenges

“…In some landscapes, multiple fire regimes may be possible. Choosing the appropriate fire regime to promote or sustain will depend on both long-and short-term social and ecological effects [9,[43][44][45]. Cultural values derived from fire-affected landscapes are relative to the preferences and incentives for different social groups and individuals.…”

Preferential Production and Transport of Grass-Derived Pyrogenic Carbon in NE-Australian Savanna Ecosystems

“…However, a decreasing trend in global area being burnt has been reported over the past 18 years, which appears to be significant in grass-dominated ecosystems (Andela et al, 2017). Understanding past fire regimes and the main factors driving fire dynamics is important to better manage biodiversity and ecosystem functions (Conedera et al, 2009;Santín and Doerr, 2016). It is equally relevant to improve our knowledge of recent pyrogenic carbon (PyC) dynamics, including the provision of accurate information on PyC formation, transport and deposition, which is fundamental to better understand a significant slow-cycling component of the global carbon cycle (Bird et al, 2015).…”